I've spent many years riding bikes but it appears that my knowledge of drive chains is somewhat lacking. Fortunately, I have a couple hundred thousand online acquaintances who may be able to set me straight.

So as I understand it, there are basically three types of chains: conventional, o-ring, and x-ring. Conventional chains need to be lubed on a regular basis but the o and x ring varieties are sealed and don't need to be lubed but obviously need to be kept clean. Am I on the right track so far?

The reason for my questions is because I just bought an o-ring chain and the instructions on the box say to lube it with 90wt oil every 300-400 miles. Is there a way to visually determine if a chain is conventional or o/x ring?

I believe if you look just inside the plate holding the pin, you should be able to see the o-ring or x-ring. See picture below.

From various websites, the thought is it is necessary to lube the X or O rings to stop them from drying out and cracking, which will allow the lubrication to escape past the rings. A clean with a soft brush (not wire brush as it can break the seals) and a light lube is what I have read.